Vehicles such as a conventional mobile aerial work platform, particularly those that include a boom, are frequently maneuvered into locations that are in close proximity to structures, supplies or other obstacles. Conventionally, such vehicles are maneuvered using a steering axle and a propulsion source driving at least two wheels in the same direction at approximately the same speed. Accordingly, these conventional vehicles are maneuvered by driving forward and backward while turning or pivoting the wheels on the steering axle. It is often difficult for such vehicles to maneuver into tight locations and/or get optimally oriented at the location to provide maximum load lifting capabilities.
Vehicles such as a conventional mobile aerial work platform, particularly those that include a boom for a platform or a telehandler, typically have an upper swing chassis supporting the lifting structure that rotates relative to the driving chassis of the vehicle on a vertical axis to allow access for the lifting structure to sweep through 360 degrees of range without repositioning or driving the vehicle. These vehicles typically have a rectangular footprint and stability is reduced when the boom is rotated to the side of the vehicle and counterweight or other ground supports must be added to maintain stability.
Some other conventional vehicles are maneuvered with a so-called skid steer system that drives wheels or tracks on opposite sides of the vehicle in different directions or at different speeds. Because the wheels or tracks of skid steer vehicles do not pivot, there is a portion of the driving traction that does not coincide with a turning path. This effect is generally referred to as “scrub” or “scrubbing” and can result in excessive wheel wear and/or terrain damage.